An electron spin resonance (ESR) measurement system for use at ultralow temperatures using a 3He-4He dilution refrigerator has been developed down to 160 mK. As the first experiment, the ESR was measured on a quantum spin chain Cu benzoate, in which a field-induced gap was recently found. The evaluation of a new ESR mode, so-called breather mode, was found at the lowest temperatures. In the present work, we observed a smaller gap in H||b by suppressing of the thermal excitation.
- Dilution refrigerator
- Electron spin resonance
- Quantum spin chain
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering